FOSSweb Teacher videos

Balance and Motion

• Balance and Motion is a 1st grade kit designed to introduce/reinforce physical science concepts.
  • Topics include balance, linear and rotational motion.
• In general, this kit can be divided into three parts:
  • Balance - Students learn about balancing objects, using counterweights, and the stability of a balanced object.
  • Motion - Students learn about how different objects move in different ways
    • Spinners: In this investigation, students make their own tops, zoomers and twirlers to example rotational motion. They also learn about force, axes, and how mass affects the stability of spinning objects.
    • Rollers: Here, students learn about how wheel size affects the path of a rolling system. They discover the placing weights in different places affects how something moves. Lastly, in order to discover how to make a cool roller-coaster, students make marble
• Additional materials not provided by the kit : pliers (to make the aluminum wires safer for the kids)

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Possible Lesson Plan

• Kits tend to have more lessons than we have time to get through. Some lessons can be combined with others, or omitted entirely. Here is where we can suggest the 10 or so lessons for fellows to get through. If you are teaching this kit to 1st graders early in the year, remember that they are more like old kindergartners and some activities will have to me modified or omitted. Below is an alternative schedule that skips the lesson where students make mobiles (1.4) because teachers thought it might be too much.
  • Suggested Schedule
    Day 1: Investigation 1.1
    Day 2: Investigation 1.2
    Day 3: Investigation 1.3
    Day 4: Investigation 1.4
    Day 5: Investigation 2.1
    Day 6: Investigation 2.2 (Skip this one if you need to cut a lesson)
    Day 7: Investigation 2.3
    Day 8: Investigation 3.1
    Day 9: Investigation 3.2
    Day 10: Investigation 3.3
  
  
  • Alternative Schedule
    Day 1: Intro/DEMO
    Day 2: Investigation 1.1
    Day 3: Investigation 1.2
    Day 4: Investigation 1.3
    Day 5: Investigation 2.1
    Day 6: Investigation 2.2
    Day 7: Investigation 2.3
    Day 8: Investigation 3.1
    Day 9: Investigation 3.2
    Day 10: Investigation 3.3

Schedule used for a school that had four day weeks:

1. Investigation 1.1
2. Investigation 1.2
3. Investigation 1.4
4. Investigation 2.1
5. Investigation 2.3
6. Investigation 3.1
7. Investigation 3.2
8. Investigation 3.3

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General Notes

• During a new investigation, only a few students (sometimes only one) typically figure out how to do the activity. From there, other students see those students' ideas, and use or modify it for themselves. This sharing of ideas is encouraged. Also be aware that the time needed for a given part of an investigation decreases as students progress through the investigation. For example, in 1.1 it may take students a long time to figure out ways balance the crayfish, but by 1.2 and 1.3 most of them can balance objects fairly readily.

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Kit Preparation

If you have a brand new kit, congratulations, however there are a few extra things that need to be done before you teach with it (this excludes photocopying worksheets).

• Investigation 1: Balance
  • All of the tagboard shapes need to be punched out. This includes the crayfish, triangles, arches (rainbows) and the pencil/hand.
  • It is recommended that the aluminum wires have the ends looped so that students don't accidentally poke themselves or someone else. A pair of needle-nose pliers works great for this and it only takes about 15 minutes. For a picture, see page 20 in Investigation 1.
• Investigation 2: Spinners
  • For Part 2 you will need to cut lengths of string to about 100 cm. There are quick, easy instructions on page 15 in Investigation 2.
• Investigation 3: Rollers
  • NOTE TO TEACHERS: Be aware that for Part 2 (Rolling Cups) you need to provide a penny for each student in your class. It is recommended that you have a few extra.

Restocking Notes

• Punched out tagboard pieces can be reused when gently worn.
• Cut pieces of string should be retained.

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Investigations

Investigation 1: Balance

Investigation 1.1: Trick Crayfish

Typical Duration: 50 minutes

• Overview: Students learn about balancing an object on a point (latter called the balance point).
  • Students learn to tell when something is balanced and when it's not.
  • Students begin to learn how counterweights help to balance an object.
    • Students begin to learn that the counterweights need to be low on the object in order for it to balance. Most students will not get fully grasp this until investigation 1.3 or 1.4. Form here on, this will be called the balance point and counter weight relation.
• Advice
  • Here are some suggested ways for the students to balance their paper crayfishes:
    • With the balance point on the nose, with the tail toward the ceiling. (picture in manual, side of page 12)
    • With the balance point on the inside of one of the claws with the tail pointed horizontally.
    • With the balance point on the thinnest part of the tail, with the claws pointed horizontally. (picture in manual, bottom of page 12)
  • Vocabulary is important for the students to be able to describe their ideas. Since the material is new to the students, don't hold back on having the students learn the words. Try to ask similar (if not the same) questions requiring the use of the new vocabulary a few times over the course of the lesson. This also helps them learn the material, and to think through a question to produce an answer.
• Demo ideas
• Media Clips and Links
• Extensions

Investigation 1.2: Triangle and Arch
Typical Duration: 50 minutes

• Overview: Students continue to learn about the relationship between counterweights and a balanced object.
  • The concept of stability is introduced.
• Advice
  • Let students explore with balancing the triangle and arch before giving them the handout.
    • Suggestion: After about ten minutes of exploration, start drawing any stable configurations that the students figure out on the board.
    • Suggestion: Challenge the students to try to get the shapes to balance on the corners of both shapes. The handout will be less challenging for students if they spend the first part of the lesson doing this.
  • At the end of the lesson try to lead the class into seeing the pattern in the balanced and not balanced pictures on the handout. Your goal is to get them to see that when the clothes pins are belowthe balance point, the object will balance. Most likely, they will give answers indicating the order of the shading, shape, or clothes pin direction. The last of these is the important one. If no one gives the desired answer, point out the answer like this:
    • Let's look at box 1
    • Where is the balance point? (answer: black rectangle)
    • Where is the clothes pin? (answer: at the bottom)
    • Is the clothes pin above or below the balance point? (answer below)
    • Go through the next few boxes the same way. If they still don't get it, tell them that the counter weights need to be below the balance point for the object to be balanced. You will most likely have to repeat this during the next two lessons.
  • The handout is also a great place to mention how scientists make guesses all the time, that we call a guess a "hypothesis" and that it is totally fine if you are wrong. In fact, we are often wrong, but that is okay in science.
• Demo ideas
• Media Clips and Links
• Extensions

Investigation 1.3: The Pencil Trick

Typical Duration: 50 minutes

• Overview: Students continue to learn about the relation between the balance point and counter weights, by balancing a pencil on its point.
  • Students balance a paper "pencil and arm", similar to the shapes they balanced in Investigation 1.2.
  • Students use wire and clothespins to balance a pencil on the craft stick by its tip.
  • By this point, they should start to be able to explain the relationship between the counter weight and balance point.
• Advice
  • It is helpful to review the shapes from the day before, especially the arch. Students usually can balance the drawing very quickly.
  • If you have enough materials, give the students two craft sticks and four clothespins. Have them leave their paper "pencil and arm" balanced on one craft stick, so they can refer back to it while trying to balance the real pencil.
  • Point out to the students (if they need help and don't do this right away) that the hand in the drawing is wrapped around the pencil. This may help jump-start some students if they don't get it right away.
  • You may need to supply tape to help keep the wire around the pencil.
  • Like the previous lessons, continue to go over where the counter weights need to be in relation to the balance point.
  • Be sure to emphasize that the pencils need to be balanced on their TIPS. Many students will immediately balance the pencils on their sides. Emphasize that the tip of the pencil should be the only thing that touches the craft stick.
  • This challenge is often frustrating for the students. Some who are frustrated may decide it's impossible and get off-task, but they usually try again once they find that someone else in the class has successfully balanced the pencil.
• Demo ideas
• Media Clips and Links
• Extensions

Investigation 1.4: Mobiles

Typical Duration: 50 minutes (30-40 min Science time, 10-20 min coloring and cutting)

• Overview: Students build paper wind chimes, called mobiles.
  • By this point, they should be able to explain the relationship between the counter weight and balance point.
• Advice
  • Put the straw through the skinny part of the paperclip. This way, it doesn't slide around, which keeps the mobile balanced.
  • Most of the students can make the more challenging mobile design. If you have a document camera, show them how to build it step-by-step. Start with putting the paperclips on the straws, then putting the rubberbands on the paperclips, and then bending the paperclips out so the cut up papers can be fit on them.
• Demo ideas
• Media Clips and Links
• Extensions
  • Teachers can use this design later in the year for more art projects. One teacher decided that she could use this mobile design to make mobiles for St. Patrick's Day using a rainbow, pot of gold, and a four leaf clover. This is a great way for teachers to easily review balance and stability later in the year.

Investigation 2: Spinners

Investigation 2.1: Tops

Typical Duration: 50 minutes

• Overview: Students learn that spinning an object can give the object stability.
  • Other examples of this are a basket ball on one's finger, a spinning penny
• Advice
  • Some students will end up breaking the shafts. That's why the kit has so many. However, the spinners still work pretty well if they have a shorter straw. They tend to be more balanced.
  • Some brands of shafts are a little to small to fit snugly into the disks.
  • The best top will probably have lots of weight toward the bottom of the shaft.
• Demo ideas
  • Bike wheel and turn table
  • Spin a coin on the table top
• Media Clips and Links
• Extensions

Investigation 2.2: Zoomers

Typical Duration: 50 minutes

• Overview: Students learn that linear motion can create a spinning motion.
• Advice
  • Students will likely need help getting their zoomers into the starting position.
  • You will likely find yourself helping the students with their hand coordination.
  • It is definitely true that making the zoomers with the red disks only can hurt the kids fingers (some might even get blisters if they get too into it), so adding the small yellow disks to the loops does save their fingers. However getting them to correctly assemble the zoomers using two yellows and a red is difficult. You may want to assemble them beforehand.
  • Some of the smaller students may find it easier to get their zoomers going with shorter pieces of string (80 - 90 cm).
• Demo ideas
• Media Clips and Links
• Extensions

Investigation 2.3: Twirlers

Typical Duration: 50 minutes

• Overview: Students observe that an object falling through the air can begin to spin.
• Advice
  • Before the students cut up the paper for the twirlers, have them trace the lines they need to cut with a crayon. They are much less likely to cut on a line that they shouldn't.
  • If you have time: Once the students get their twirlers to spin, challenge them to get their twirlers to spin in the opposite direction.
  • Even if some students end up with the a properly created twirler, it might not work. This is usually due to them bending the paper in places that it shouldn't be bent. Another reason might be that the wings aren't bent to the same degree.
  • Describing 'air resistance' is pretty difficult. Students will use terms like wind and blow. This is where the difficulty comes in, since there is likely no moving air in the room. A analogy with water might be useful.
    • Alternatively, I had a teacher drop a crayon at the same time as she dropped the twirler. She asked the students if the twirler and the crayon fell at the same speed (no). Then she asked what was different between the twirler and the crayon (the twirler has wings). Then she asked what was pushing the wings up (the air). She then said that when the air pushes the wings up, we call it air resistance.
• Demo ideas
• Media Clips and Links
• Extensions

Links

Balance and Motion toolkit Created by WA State LASER program. Includes key concepts, kit set up and management, teacher tips, literacy tips.